As wireless devices and associated wireless networks become ubiquitous in the lives of professionals and consumers, increasing concern has been expressed regarding exposure to radiofrequency radiation. For example, concerns have been expressed about cancer and cellular telephone usage. As use of other wireless devices, such as wireless headsets, wireless pad devices, laptops, game console controllers, wireless mice and keyboards, among other devices, concern has been extended to the influence of various wireless frequencies on the body and its functions.
Accordingly, regulators have sought to limit exposure, measured as a specific absorption rate (SAR), when using wireless devices. Various national and regional standards bodies have implemented specific absorption rate (SAR) thresholds or ranges Manufacturers are tasked with making devices that do not violate the regulated SAR ranges.
To reduce SAR, manufacturers sought to reduce transmission power or to cycle transmissions in the time-domain. However, reducing transmission power can lead to airtime inefficiencies and performance degradation. Similarly, time-domain duty cycling can reduce performance.
The use of the same reference symbols in different drawings indicates similar or identical items.